Chronic stress in particular has significant implications for numerous chronic diseases, including depression, anxiety, cardiovascular disease, autoimmune disorders and disorders of aging. Researchers at Brigham and Women’s Hospital (BWH) have found that women and men’s brains handle stress differently, altering the way each gender may experience these diseases. These findings appear online on Jan. 13, in the Journal of Neuroscience.
Using functional magnetic resonance imaging (fMRI), researchers looked at the brain activity of healthy men and women while they viewed images acting as stressful stimuli. Women underwent the scanning twice, once during the beginning of the menstrual cycle and once during ovulation and their results were then compared to the men’s fMRI results. Brain activity in response to stress looked similar in men compared with women at the beginning of the women’s menstrual cycle. However, brain activity in response to stress was much higher in men compared to that of the same woman during ovulation.
“We found that women have been endowed with a natural hormonal capacity to regulate the stress response in the brain that differs from men,” said lead study author Jill Goldstein, PhD,
director of Research for the Connors Center for Women’s Health and Gender Biology at BWH and professor of Psychiatry and Medicine at Harvard Medical School. The largest differences were seen in brain regions known to control the autonomic arousal response in the brain. Findings suggest that sex differences in stress response circuitry are hormonally regulated through the control of arousal. “The results were striking given that the men and women reported experiencing the stressful stimuli similarly even though their brains were activating differently. “
“Diseases that are affected by stress often present differently in men and women,” said Goldstein. “Therefore, understanding sex differences in stress regulation in the brain can provide clues to understanding the nature of these chronic medical disorders. Mapping out sex-specific physiology in the brain will also provide the basis for the development of sex-specific treatments for these diseases.”
Although some previous studies in animals demonstrated sex differences in stress response, these findings had not been demonstrated in the human brain prior to this study. Goldstein added, “This not only demonstrates sex differences in stress response in the brain, but also provides clues to the basic physiological differences in the male and female brain and how some areas of the brain function differently in men and women.”
The study was funded by a grant to Goldstein and colleagues from the National Institutes of Health Office for Research on Women’s Health and the National Institute of Mental Health.